Muffler



FIG. 1 is a first perspective view of an ornamental design for a muffler, according to the invention.

FIG. 2 is a front view of a muffler of FIG. 1.

FIG. 3 is a back view of a muffler of FIG. 1.

FIG. 4 is a left view of a muffler of FIG. 1.

FIG. 5 is a right view of a muffler of FIG. 1.

FIG. 6 is a top view of a muffler of FIG. 1; and,

FIG. 7 is a bottom view of a muffler of FIG. 1.

The shading and contour lines in FIGS. 1-7 are for illustrative purposes only and form no part of the claimed design. 

CLAIM The ornamental design for a muffler, as shown and described. 